Articles such as beverages or other consumer product containers are often wrapped in packages holding a number of the articles before they are placed on a pallet or divided into laned flows. Therefore, groupings of 6, 12 or 24 bottles for example may be created and held together via stretch or shrink wrapped plastic, boxes, and/or blanks. These groupings are then oriented in some fashion to create a pallet load or laned flow.
Typically, the groupings are fed out of a wrapping or other packaging source individually in a uniform fashion (all aligned the same way) and at a uniform rate (all at the same speed and with the same spacing between them). Various devices have been proposed to take the groupings in such a uniform stream and to place them as desired laterally within the stream (for example by moving a grouping left or right from a feed location) and to orient them within the stream (for example by turning a grouping 90 degrees) such that they form a desired pallet layer downstream or such that they are placed into lanes for further processing downstream. Such concepts can also apply to individual articles, such as boxes, that are to be palletized. Thus, as noted herein an article may be a single item (such as a box or other item) or may include a grouping or articles such as a twelve-pack grouping of containers.
Such placement and orientation can be provided by robot arms, by gantry devices, by orienting conveyors, by pushers or other equipment, or even by hand. When robot arms or gantry devices are used, the end effectors may have an optional grasping function, wherein an article can be grasped between two opposing plates and the article can then be moved to a desired location and/or oriented in a desired way. One or both of the plates can move so that the article is squeezed just tightly enough to move and place the article, and each such article is moved and placed individually.
In one common system, as shown in FIG. 13A, flow enters from the left as shown on a first conveyor 10, is transferred to a higher speed gapping conveyor 12 to spread out articles in the direction of travel, and is transferred to a further conveyor 14 where orientation occurs in some fashion. Note that articles A1, A2 and A3 may or may not be substantially spread apart, while articles A4-A9 are uniformly spread apart. Such arrangement would typically occur where a constant speed gapping conveyor 12 and further conveyor 14 are running faster than constant speed first conveyor 10. In such a conventional system, individual articles are placed and oriented one at a time, as noted above.
In another conventional system of FIG. 13B, gapping conveyor 12 is a “surge” conveyor driven at a non-constant speed in order to group two articles more closely together for handling at once to save placement steps in forming a pallet layer or in laning. However, use of a non-constant speed conveyor 12 can introduce stability issues for articles, and the ultimate placement of articles on conveyor 14 may be inconsistent due to acceleration and frictional issues.
Accordingly, improved methods and systems would be welcome for arranging articles on a conveyor for forming a pallet layer or laning, addressing drawbacks of conventional systems or other issues.